A Mumbai diver didn't even know Apple Watch Ultra had a siren until it automatically started and saved his life.
It's not the best known or most publicized feature of the Apple Watch Ultra, but every model to date has come with an 86-decibel siren alarm. Apple designed it to start blasting out either when the user turns it on or, as in this case, when they are incapacitated and the Apple Watch Ultra's depth sensor determines there's a problem.
According to India Today, Kshitij Zodape was SCUBA diving over the summer, swimming in the Bay of Bengal near Puducherry. When he was at around 120 feet down in the ocean, a weight belt he was wearing came unstuck.
The loose belt didn't just stop him diving lower, it actually propelled him back up toward the surface.
"The water was very choppy and visibility was poor, we could see only 5 to 10 meters," he said. "We were about 36 meters down when I suddenly started shooting up towards the surface."
How Apple Watch Ultra's siren saved the diver's life
Even as Zodape says he wasn't able to understand what was happening, his Apple Watch Ultra's depth sensor detected the rapid vertical ascent. It sent him an emergency notification, but he wasn't able to stop rising.
The siren feature on Apple Watch Ultra
"Before I could even realise, my watch started showing warnings. It told me that I needed to slow down because my ascent was too quick and it could cause injury," he continued. "I couldn't control [what was happening], I was still rising rapidly."
When he failed to respond and continued to rise, the Apple Watch Ultra sounded its siren. It was this that got the attention of a diving instructor who was with Zodape.
That instructor was able to reach Zodape and prevent him rising any further. At the depth Zodape was originally, his body was under pressure and too fast a rise to the surface would have made his lungs expand and potentially rupture.
Following what could have been a fatal accident, Zodape wrote to Apple to thank them for this feature he says he didn't even know about.
"I'm so glad your instructor heard the alarm and quickly assisted you," replied Tim Cook. "Thanks so much for sharing your story with us. Be well."
